package cc.openhome;
import java.util.InputMismatchException;
import java.util.Scanner;
public class Average2{
    public static void main(String[] args) {
        try {
            Scanner console=new Scanner(System.in);
            double sum=0;
            int count =0;
            while (true){
                int number=console.nextInt();
                if (number==0){
                    break;

                }
                sum+=number;
                count++;

            }
            System.out.printf("平均%.2f%n",sum/count);
        }catch (InputMismatchException ex){
            System.out.println("必须输入整数");
        }
    }
}